In high speed digital-analog conversion (DAC) applications, unwanted spurs often occur at divides of the DAC output frequency. Such spurs predominantly occur at power of two (so 2, 4, 8 etc) divides of the DAC output frequency. For upsampling DACs, the frequency bands that can be selected are usually a multiple of such a divide (such as an integer multiple of ⅛th of the DAC output frequency).